IAEA-TECDOC-1658
Viability of Sharing Facilities for the Disposal of Spent Fuel and Nuclear Waste
INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA
ISBN 978–92–0–113310–6 ISSN 1011–4289
IAEA-TECDOC-1658 n VIAbIlITy Of ShArIng fACIlITIES fOr ThE DISpOSAl Of SpEnT fuEl AnD nuClEAr WASTE
spine = 76 Seiten = 4 mm
VIABILITY OF SHARING FACILITIES FOR THE DISPOSITION OF
SPENT FUEL AND NUCLEAR WASTE
AFGHANISTAN ALBANIA ALGERIA ANGOLA ARGENTINA ARMENIA AUSTRALIA AUSTRIA AZERBAIJAN BAHRAIN BANGLADESH BELARUS BELGIUM BELIZE BENIN BOLIVIA
BOSNIA AND HERZEGOVINA BOTSWANA
BRAZIL BULGARIA BURKINA FASO BURUNDI CAMBODIA CAMEROON CANADA
CENTRAL AFRICAN REPUBLIC CHAD CHILE CHINA COLOMBIA CONGO COSTA RICA CÔTE D’IVOIRE CROATIA CUBA CYPRUS
CZECH REPUBLIC DEMOCRATIC REPUBLIC OF THE CONGO DENMARK
DOMINICAN REPUBLIC ECUADOR
EGYPT EL SALVADOR ERITREA ESTONIA ETHIOPIA FINLAND FRANCE GABON GEORGIA GERMANY
GHANA GREECE GUATEMALA HAITI HOLY SEE HONDURAS HUNGARY ICELAND INDIA INDONESIA
IRAN, ISLAMIC REPUBLIC OF IRAQ
IRELAND ISRAEL ITALY JAMAICA JAPAN JORDAN KAZAKHSTAN KENYA
KOREA, REPUBLIC OF KUWAIT
KYRGYZSTAN LATVIA LEBANON LESOTHO LIBERIA
LIBYAN ARAB JAMAHIRIYA LIECHTENSTEIN
LITHUANIA LUXEMBOURG MADAGASCAR MALAWI MALAYSIA MALI MALTA
MARSHALL ISLANDS MAURITANIA MAURITIUS MEXICO MONACO MONGOLIA MONTENEGRO MOROCCO MOZAMBIQUE MYANMAR NAMIBIA NEPAL
NETHERLANDS NEW ZEALAND NICARAGUA NIGER NIGERIA
NORWAY OMAN PAKISTAN PALAU PANAMA PARAGUAY PERU PHILIPPINES POLAND PORTUGAL QATAR
REPUBLIC OF MOLDOVA ROMANIA
RUSSIAN FEDERATION SAUDI ARABIA SENEGAL SERBIA SEYCHELLES SIERRA LEONE SINGAPORE SLOVAKIA SLOVENIA SOUTH AFRICA SPAIN
SRI LANKA SUDAN SWEDEN SWITZERLAND
SYRIAN ARAB REPUBLIC TAJIKISTAN
THAILAND
THE FORMER YUGOSLAV REPUBLIC OF MACEDONIA TUNISIA
TURKEY UGANDA UKRAINE
UNITED ARAB EMIRATES UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND UNITED REPUBLIC OF TANZANIA
UNITED STATES OF AMERICA URUGUAY
UZBEKISTAN VENEZUELA VIETNAM YEMEN ZAMBIA ZIMBABWE
The Agency’s Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations The following States are Members of the International Atomic Energy Agency:
IAEA-TECDOC-1658
VIABILITY OF SHARING FACILITIES FOR THE DISPOSITION OF
SPENT FUEL AND NUCLEAR WASTE AN ASSESSMENT OF RECENT PROPOSALS
INTERNATIONAL ATOMIC ENERGY AGENCY
VIENNA, 2011
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IAEA Library Cataloguing in Publication Data
Viability of sharing facilities for the disposition of spent fuel and nuclear waste : an assessment of recent proposals. – Vienna : International Atomic Energy Agency, 2011.
p. ; 30 cm. – (IAEA-TECDOC series, ISSN 1011-4289 ; no. 1658)
ISBN 978-92-0-113310-6
Includes bibliographical references.
1. Radioactive waste facilities. 2. Radioactive waste disposal – Management. 3. Spent reactor fuels – Management.
I. International Atomic Energy Agency. II. Series.
FOREWORD
For a long time, ideas have been put forward and initiatives launched regarding cooperation in the nuclear fuel cycle, including both regional and multilateral approaches, to dealing with reprocessing, storage of spent fuel or, more recently, disposal of radioactive waste. The rationale behind the multinational disposal concepts ranges from concerns about the capability of some countries to implement safe national nuclear waste management programmes in a timely fashion, to questions about the availability of suitable geological formations; and, of course, the economies of scale in repository implementation are a major driver.
In addition to these issues of cost, environmental and safety considerations, other benefits of such approaches for storage and underground disposal are security and non-proliferation advantages, which have become increasingly important after recent terrorist events worldwide. The IAEA has supported, since the 1970s, multilateral initiatives that seek to reduce access to weapons usable nuclear material technologies.
Among different cooperation concepts, the sharing of facilities for dealing with radioactive waste management was proposed and developed through conferences and expert group meetings, as well as technical publications. The experience gained in other international frameworks, such as groupings in the European Union, was also reviewed. It was concluded that the scenarios and approaches proposed in earlier IAEA publications require further consideration regarding the conditions for their implementation, their viability, and the benefits and challenges inherent in the alternatives proposed.
It is useful to consider the wider issue of spent fuel disposition (reprocessing/encapsulation, storage and disposal) when discussing the option of shared repositories for the disposal of spent fuel and high level waste from reprocessing. This proper account to be taken of new initiatives and technologies in predisposal activities and their impact on the viability of developing shared disposal facilities. To encourage discussion on this topic, relevant information has been updated and is presented in this report.
The IAEA would like to express its thanks to all participants involved in the drafting of this report. Special thanks are due to C. McCombie (Switzerland) for his leading role in discussions during the consultants and technical meetings, and for his contribution in drafting and finalizing this report.
The IAEA officers responsible for this report were B. Neerdael and S. Hossain of the Division of Nuclear Fuel Cycle and Waste Technology.
EDITORIAL NOTE
The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries.
The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA.
CONTENTS
SUMMARY ... 1
1. INTRODUCTION ... 3
1.1. Background ... 3
1.2. Early studies on multinational approaches ... 5
1.2.1. Disposal Studies ... 5
1.2.2. Multinational storage options ... 7
1.3. Recent developments in multinational approaches ... 7
1.4. Objectives of the report ... 8
1.5. Scope of the report ... 9
1.6. Structure ... 9
2. NUCLEAR POWER AND NUCLEAR FUEL CYCLE DEVELOPMENTS AS DRIVERS FOR MULTINATIONAL INITIATIVES ... 10
2.1. Introduction ... 10
2.2. Technological spent fuel disposition options ... 11
2.3. Reactor technology considerations ... 12
2.4. Impacts of new reactors and fuel cycles on geological disposal ... 14
2.5. Influence of new fuel cycles on multinational approaches ... 16
3. RECENT DEVELOPMENTS IN MULTINATIONAL INITIATIVES ... 18
3.1. International strategic studies and reports ... 19
3.1.1. MNA Expert Group ... 19
3.1.2. WNA views on security of supply at the back end of the fuel cycle ... 20
3.1.3. Proposals at the 2006 IAEA General Conference ... 21
3.1.4. US National Academies and Russian Academy of Sciences initiatives ... 22
3.2. Current specific add-on and leasing initiatives ... 23
3.2.1. US GNEP proposal ... 23
3.2.2. Russian GNPI proposal ... 26
3.3. Current specific partnering initiatives ... 27
3.3.1. SAPIERR Project ... 27
3.3.2. Arius Association ... 30
3.4. Other proposals ... 31
4. IMPACTS OF NEW MULTINATIONAL INITIATIVES ON VIABILITY OF SHARED FACILITIES FOR THE DISPOSITION OF SPENT FUEL AND NUCLEAR WASTES ... 32
4.1. Impact of MNA recommendations ... 32
4.2. Impact of GNEP ... 34
4.3. Impact of Russian GNPI initiative ... 35
4.4. Impact of SAPIERR ... 37
4.5. An example of multinational agreement ... 38
5. SELECTED KEY ISSUES ... 41
5.1. Siting strategies ... 41
5.2. Regulatory and legal aspects ... 43
5.3. Liabilities and long term rights ... 44
5.4. Fair funding mechanisms ... 45
5.5. Safety and security ... 47
5.6. Timing of repository implementation ... 48
5.7. Public and Political Attitudes ... 48
5.8. Potential impacts on national programmes ... 53
5.9. Role of IAEA and other international organizations ... 53
6. CONCLUSIONS AND FUTURE OUTLOOK ... 54
6.1. Conclusions ... 54
6.2. Future work ... 57
6.2.1. Specific suggestions related to ongoing initiatives ... 57
6.2.2. Overarching considerations ... 59
REFERENCES ... 61
CONTRIBUTORS TO DRAFTING AND REVIEW ... 65
SUMMARY
The long-term management of waste at the back-end of the nuclear fuel cycle remains one of the most critical issues affecting the acceptance of nuclear power and consequently the challenges associated with the global expansion of nuclear power. A full solution to the responsible long term management of the waste implies a credible disposition strategy, an institutional framework to allow its implementation and the scientific, technical and industrial capabilities to carry out the necessary activities. Safe and secure repositories are needed not only for countries with nuclear power programmes but also from the many additional countries that produce long-lived wastes from other nuclear applications in research, medicine and industry. Those countries may encounter some difficulties to develop or to implement a national strategy. One approach to avoid this situation would be the implementation of multinational or regional facilities. These have been recognized to have potential advantages in the areas of safety, nuclear security, non-proliferation, environmental impact and economics.
The main objective of this document is to give an updated overview of changing global attitudes towards nuclear power and of potential developments in the nuclear fuel cycle, with a view to assessing how these changes may influence the viability of establishing multinational disposition approaches for spent fuel. In this report the earlier work done on multinational initiatives for storage and disposal is referred to but it is not repeated in the detail. Instead, recent initiatives are described and their impacts on the viability of implementing multinational disposal facilities in the future are assessed.
Following the introductory Chapter, relevant aspects of the nuclear fuel cycle and some of the recently proposed developments that affect spent fuel disposition are described in Chapter 2.
Technological alternatives for spent fuel disposition have been spelled out, all of which lead to a need for geological disposal that will require safety demonstration. The developments in reactor and fuel cycle technologies will have direct impacts on disposal, in both a technical and a strategic manner. At a technical level, the advanced approaches will change the nature and the volumes of long-lived radioactive wastes. Positive aspects are that smaller or fewer geological repositories may be needed. However, the new waste forms need to be properly characterized, in particular with respect to their long term behaviour. The advanced technologies and complex infrastructures needed for preparing new fuels and for advanced processing of spent fuel imply that multinational approaches will almost certainly be necessary in these areas since the capabilities will not be established in all countries.
Specific initiatives that have been proposed in recent years in order to make the fuel cycle more international are discussed in Chapter 3. Most of these multinational approaches have been focused on controlling the front end of the fuel cycle (enrichment) and on reprocessing, since these are the most sensitive technologies that would clearly be best restricted to a limited number of locations. The focus of the present report, however, is on the specific impacts of the proposed approaches on spent fuel disposition, and especially on the feasibility of multinational geological repositories.
All of the various initiatives described in Chapter 3 are currently theoretical concepts or at most study projects related to the possibilities for multinational cooperation. In Chapter 4, they are assessed with respect to their potential impact on the viability of multinational spent fuel disposal facilities. For each, an overview is produced of their strengths and weaknesses.
Selected critical issues to be faced in implementing multinational repositories are addressed in Chapter 5. Specific key issues have been identified as being sensitive or challenging by nature, not in a technological sense, but from a sociological perspective. All these issues are discussed in depth, along with drivers and frames that affect the disposal of spent nuclear fuel and long-lived and high-level waste.
Finally in Chapter 6 conclusions are formulated and suggestions are made for the future. The report concludes that multinational shared disposition facilities are a viable approach to enhancing the economics, safety, security and non-proliferation aspects for nuclear power globally. Legacy and other wastes have to be safely disposed of and small and new nuclear Member States are looking at partnering. Nuclear security concerns have led to new proposals and initiatives that further expressed the need for global cooperation to make safe disposal available in due time to all Member States.
All States should recognize that secure spent fuel disposition is an essential element of all nuclear power programmes, that the problem is global in nature but also that a solution is mandatory. International cooperation should be strengthened in order to achieve this global solution and the involvement of international organizations further stimulated. International cooperation should, however, never be used as an argument to postpone a decision or to establish a wait-and-see approach.
1. INTRODUCTION 1.1. Background
Responsible use of nuclear power requires that – in addition to all of the safety, security and environmental protection measures associated with power plant operation – credible solutions are developed for dealing with the wastes produced. These wastes include spent fuel (SF), if it is regarded as waste, high level waste (HLW), if reprocessing is carried out, and all other radioactive wastes produced as a result of nuclear power production. A full solution to the responsible long term management of the wastes implies a credible spent fuel disposition1 strategy, an institutional framework to allow its implementation and the scientific, technical and industrial capabilities to carry out the necessary activities.
There are no operating geological repositories for final disposal of spent fuel or of HLW resulting from reprocessing spent fuel. The fundamental feasibility of implementing safe repositories is questioned by a significant fraction of the population in most countries.
Accordingly, spent fuel disposition remains perhaps the most critical unresolved issue affecting the acceptance of nuclear power and consequently the challenges associated with the global expansion of nuclear power.
There is a technical consensus that the end point for spent fuel disposition must include geological disposal, either of the spent nuclear fuel itself or of long lived waste products produced by reprocessing the fuel. This is the only approach judged feasible for providing the necessary long term passive protection of humans and the environment.
The geological repository is likely, in turn, a sensitive aspect in spent fuel disposition. In some advanced countries, great progress has been made towards implementation of geological repositories for SF/HLW disposal. For example in Finland, Sweden, and France the most challenging step − identifying a final repository site − is at or near completion. Although some countries have been able to make progress towards a national spent fuel disposition system, many have scarcely begun and several national programmes are blocked for political, technical or economic reasons, with no clear path forward. In all cases, the implementation process is long and complex and the costs that will be involved in construction and operation of the facilities are high.
For some national nuclear programmes – in particular small or new nuclear programmes – repository implementation can be especially difficult. Furthermore, the inventories of HLW or
1 It should be noted that this is a wider definition than is used in many other reports (see the box above)
“Spent fuel disposition” is understood in this report to encompass all activities following the discharge of the spent fuel from a reactor core, including any storage at the reactor site or away from the reactor, transportation, any reprocessing and subsequent recycle activities, the conditioning of spent fuel or any remaining waste materials, the interim storage of the conditioned wastes or spent fuel and the final disposal.
SF in such countries grow slowly, so that it can be many decades before enough waste is accumulated to justify beginning with disposal. To bridge this gap, dry or wet storage capabilities for spent fuel can be constructed centrally or at reactor sites and these allow time for the necessary difficult decisions to be prepared and acted on. During this time, however, spent fuel will be stored at the surface in many diverse locations around the world. Although, with the investment of sufficient resources, the individual facilities can be constructed and operated in a safe and secure manner, their large number may pose an unnecessary potential global safety and security threat. One approach to avoid this situation would be the implementation of multinational facilities. These have been recognized to have potential advantages in the areas of safety, security, environmental impact and economics [1-4].
Already in the 1970s, the IAEA supported multinational initiatives for these reasons. When the concept became again topical at the beginning of this decade, IAEA support continued. A key technical document, “Developing multinational Radioactive Waste repositories:
Infrastructural framework and scenarios of cooperation” [5] was published in 2004 and summarized the status at that time.
In the intervening years, several developments have altered the global nuclear framework in a way that increases interest in nuclear power, in geological disposal and in multinational approaches to achieving this.
Firstly, there has been a marked increase in the nuclear power ambitions of existing nuclear energy nations and of new countries considering introducing nuclear power. This reflects:
• surging demands for energy in general, and especially for electricity, resulting from economic development and population growth;
• the improved technical efficiency and economic viability of electricity from existing plants around the world;
• energy security concerns as global demand increases for petroleum and natural gas; and
• increased awareness of the impact of carbon dioxide emissions on the global climate and weather.
Spreading nuclear power to numerous nations will require a global framework and extensive multinational cooperation if safety standards are to be maintained from power plant operation through to final disposition. For all countries using nuclear power, safety is a global issue since history has illustrated dramatically how nuclear accidents in any country can severely impact acceptance in all others.
Secondly, there has also been a continuing debate about nuclear proliferation and security risks. This debate has been fuelled by concerns about the spread of nuclear technology making it easier for States to break or withdraw from the Non-Proliferation Treaty (NPT) and to initiate nuclear weapons programmes and by the growth in international terrorism. The most immediate concerns are related to enrichment and to reprocessing technologies that could extract plutonium from spent nuclear fuel. Concentrating SF/HLW at fewer, well secured locations rather than having it widely distributed lowers the risks of its misuse by terrorists.
The third and newest point is that interest has grown in advanced reactor types and advanced fuel cycles. This arises for a number of reasons:
• If nuclear power plants are to spread throughout the world, then more efficient fuel use, improved passive safety systems and proliferation-resistant reprocessing routes are key goals.
• In the beginning of the 2000s, the U.S. retreated from the strongly anti-reprocessing stance that it took for some decades and is now considering closed fuel cycles in its national strategy. Since the USA also controls the actions taken by foreign users of US fuel technology, any developments will also influence the availability of the reprocessing option available in other countries.
• New back-end processing may result in waste streams that reduce the real or perceived burden of demonstrating the safety of geological repositories over long times. It may also ultimately result in waste streams that offer more flexibility in developing concepts for national or multinational repositories.
Ensuring that the benefits of nuclear power can be offered around the world on a much larger scale than at present requires that the complete nuclear fuel cycle, including the final disposal step, must be based to a far greater extent than hitherto on multinational cooperation.
This has led to a number of new initiatives and projects which are described in the present report. The objective is then to assess their specific impacts on the viability of multinational facilities for disposal of spent fuel or of the waste products resulting from its processing.
1.2.Early studies on multinational approaches 1.2.1. Disposal Studies
The IAEA-TECDOC-1413 [5] was published with the aim of providing a reference document for Member States potentially interested in multinational repository concepts as hosting, partner or third party countries. The main objectives of the document were to develop potential scenarios of cooperation that might be applied for the implementation of multinational repositories and to define the requirements that should be followed by Member States interested in pursuing such a cooperative effort. Three main scenarios were identified as potentially feasible and were described in the document.
The first is the cooperation scenario in which a shared repository is developed by a group of partner countries. Two or more countries join in a mutual agreement on building a repository in one or more of the participating countries, rather than having a national facility in each and every country. If a group of countries belong to the same geographical region, a repository can be called a regional repository; otherwise, it is called multinational repository.
The next option is an add-on scenario which assumes that a host country that has already implemented a national repository at some later stage offers to complement its national inventory of wastes for disposal by wastes imported from other countries. Motives for such a decision could be of an economic nature — share or decrease disposal costs — or related to safety and security. In practice, in the add-on scenario, the repository remains effectively a national repository, but with a part of the nuclear waste inventory arising from another country.
In the third option, the international or supranational scenario, a higher level of control and supervision is implemented. The operation of such a repository (or network of repositories) would be fully in the hands of an international body perhaps with the governing body employing a competent industrial consortium to actually construct and operate the repository.
Each host country would, in this scenario, cede control of the necessary site to the specified international body. The additional complications of creating an extraterritorial framework and of developing a financial model that is appealing to the host country and solving the myriad technical problems associated with opening a geological repository were regarded in Ref. [5]
as making this scenario unlikely in the near-term future. However, increasing global concerns over proliferation and nuclear security today may make countries more willing to cooperate in this area and thus make the international or supranational approach more credible.
An additional concept — relatively new at the time that document under Ref. [5] was being produced in 2004 — was also mentioned, namely fuel leasing. This concept assumes that the uranium producer or fuel fabricant does not transfer title of the fuel when it is delivered to the user. Instead the fuel is leased for use in the reactor and returned to the supplier when unloaded from the reactor. Such a concept would allow all countries, even those with small nuclear programmes, to benefit from nuclear power without being faced with the challenge of managing the spent fuel and providing all necessary infrastructure by itself. However, it was recognized that for providing leasing services, the fuel supplier must be in a country that will accept the return of spent fuel from other countries, i.e. in an international repository host country, or else the fuel supplier must have access to a multinational repository in a third country.
In the report, the benefits and challenges of a multinational approach, both for the host and for the partner countries, were addressed. Important benefits and challenges were recognized in the areas of security, environmental safety, non-proliferation, economics, institutional requirements, and public acceptance and support. The principal conclusions drawn were:
(1) Multinational repositories can enhance global safety and security by making timely disposal options available to a wider range of countries. For some Member States, multinational repositories are a necessity, if safe and secure final disposal of long-lived radioactive waste is to replace indefinite storage in surface facilities.
(2) The global advantages of multinational repositories are clear and the benefits can be significant for all parties, if they are equitably shared. For individual countries, the balance of benefits and drawbacks resulting from participation as a host or as a partner must be weighed by the appropriate national decision making bodies.
(3) Implementation of multinational repositories will be a challenging task. However, there are a number of conceivable scenarios under which their development might take place.
This report endorsed the conclusions of an earlier IAEA Report [1] on this topic:
(1) The multinational repository concept does not contradict ethical considerations.
(2) The high ratio of fixed to variable costs for a repository ensures that considerable economies of scale will apply.
(3) Transport of nuclear material is so safe that the distances resulting from a multinational repository will not have a significant impact on public health.
This led to the following key recommendations:
(1) The concept of multinational repositories should continue to receive support from all countries that have an interest in a shared disposal solution.
(2) Discussion on the advantages, drawbacks and boundary conditions for multinational concepts can be initiated by interested countries without prior definition of potential host countries.
(3) Proponents of national and multi-national repository concepts should acknowledge that both types will be implemented and should try to ensure that activities undertaken in either case do not negatively impact the other.
(4) The potential interactions between recent proposals for nuclear fuel cycle centres and for multinational repositories should be studied in more depth, in particular in connection with security and safeguards issues.
Also described was a list of areas in which further work could be usefully done to advance multinational concepts. These areas included: safety and security, liabilities, legal and regulatory, economics, inventories and social sciences. The present report documents advances made in some of these areas.
1.2.2. Multinational storage options
Soon after the publication of the repository study [5], the IAEA also produced a report on multinational storage developments [6]. The following storage scenarios were looked at:
• Spent fuel is stored in a regional facility and returned at a specified time to the originating country
• Spent fuel is stored in a regional facility prior to reprocessing; HLW is returned to the originator or to a regional storage or disposal facility
• Spent fuel is stored in a regional facility and transferred directly to a regional disposal facility (in the same or another country)
The report discussed infrastructural issues of relevance, in the categories technical, economic/financial, institutional, socio-political, and ethical. In its conclusions, it was recognized that the regional spent fuel storage concept is technically feasible and potentially viable and that storing spent fuel in a few safe, reliable, secure facilities could have safeguards, and security benefits. There have been suggestions that multinational storage schemes might be more easily implemented than final disposal projects with their indefinite timescales. However, public and political opposition to accepting foreign fuel for storage has also been strong, unless definite agreements for sending the material back to the owner are in place. Moreover, modular storage systems can be implemented in any country and with dry storage technologies there are little benefits from economies of scale. Accordingly, the potential benefits of regional cooperation are judged to be greater for disposal than for pure storage facilities.
1.3. Recent developments in multinational approaches
Since the publication of the above-mentioned reports, there have been a number of important developments influencing the viability of multinational facilities for disposition of spent fuel.
The drivers for these initiatives are mixed and inter-connected. They include:
• Growing concerns that the global expansion of nuclear power could lead to spreading sensitive technologies like enrichment and reprocessing and also spreading spent fuel (with its remaining fissile material content) at numerous national locations around the world.
• The continuing difficulties of national programmes (with some limited exceptions) in identifying technically and socially acceptable sites for geological repositories, and the realization that the very long times required to bring a repository into operation exposes it to political changes before completion.
• The awareness that new or small nuclear programmes may not be able to afford to handle their spent fuel in a safe and secure manner, and that a reliable solution to spent fuel disposition is an essential part of responsible nuclear power and hence critical for the global expansion of nuclear power.
• The fact that dry storage technology for spent fuel is available everywhere at reasonable costs, meaning that spent fuel processing and repository emplacement of nuclear waste can be deferred until optimal technologies are developed and deployed.
The most relevant studies and initiatives that have been undertaken are described in Chapter 3 of this report and their impacts on the viability of multinational disposition strategies are discussed in Chapter 4. The initiatives are of greatly differing scope and depth, so that they can not be categorized in any unique way. Some are specific projects that could lead to development of shared facilities in the relatively near future. Some are merely theoretical concepts at present. Some are truly global, others restricted to specific regions of the world.
Finally some fit to the add-on scenario described in [5], whereas others are based on the cooperation scenario. The currently most concrete initiatives are as follows:
• The Multilateral Approaches (MNA) Study of an IAEA Expert Group [7]: this is an overarching strategic study looking at how multilateral approaches throughout the nuclear fuel cycle can enhance global safety and security.
• Russian initiatives such as the Global Nuclear Power Infrastructure (GNPI) initiative [8]: this is centred on proposals to establish multinational facilities providing shared ownership for enrichment, reprocessing and eventually disposal.
• The Global Nuclear Energy Partnership (GNEP) originally proposed by the USA [9]:
this is a far-reaching effort aimed at promoting the global expansion of nuclear power while minimising security risks by encouraging States to rely on assured fuel services rather than acquiring indigenous enrichment and reprocessing capabilities. Success in GNEP would result in a small number of suppliers that provide assured supplies of fresh fuel and spent fuel disposition services for the rest of the world.
• The SAPIERR projects [10, 11] established under the auspices of the European Commission: this is a project devoted to pilot studies on the feasibility of shared regional storage facilities and geological repositories, for use by European countries.
These major initiatives are described in Chapter 3, together with accounts of other recent discussions and proposals related to the topic of multinational spent fuel disposition.
1.4. Objectives of the report The objectives of the report are:
• To give an updated overview of changing global attitudes towards nuclear power and of potential developments in the nuclear fuel cycle, with a view to assessing how these changes may influence the viability of establishing multinational disposition approaches for spent fuel
• To summarise recent international developments specifically aimed at enhancing multinational cooperation in the nuclear fuel cycle in general, and particularly in concepts related to final disposition of spent nuclear fuel
• To comment on how and when such developments might influence the viability of multinational approaches
• To address in more detail some of the key open technical and strategic issues that were identified already in earlier IAEA work and that strongly affect the probability of success of multinational approaches
• To identify areas in which further work could be done to advance the progress of multinational approaches towards the final disposition of spent nuclear fuel.
1.5. Scope of the report
In this report the earlier work done on multinational initiatives for storage and disposal is referred to but it is not repeated in the detail included in the corresponding TECDOCs 1021, 1413 and 1482 [1, 5, 6]. Instead, recent initiatives are described and their impacts on the viability of implementing multinational disposal facilities in the future are assessed. This assessment is based on examination of the strengths of the proposals and the opportunities they provide for advancing multinational initiatives. However, it considers also their weaknesses and the threats that they might pose for national disposition programmes or for multinational cooperation prospects.
In principle, the disposition of spent fuel can involve various types of nuclear facilities, including reprocessing plants, storage facilities, encapsulation plants and repositories – all of which can be national or multinational. The focus of this report, however, as of its predecessor reports in 2004 and 1998, is on disposal facilities. The reason for this is that this final step in disposition has proven to be the most challenging of all – not in a technological sense, but in a sociological context. Lack of public confidence in safe disposal and the absence of any geological repositories for SNF/HLW are the two factors most often cited today as arguments against nuclear power. Furthermore, safe and secure repositories are needed not only for countries with nuclear power programmes but also from the many additional countries that produce long-lived wastes from other nuclear applications in research, medicine and industry. Several of the specific key issues on multinational repositories that have been identified in work to date to be of an especially sensitive or challenging nature are discussed in more depth in this report. Finally, conclusions based on the analyses are presented and suggestions are made for further work that could advance the progress of multinational cooperation in spent fuel and radioactive waste disposition.
1.6. Structure
Following this introductory Chapter, relevant aspects of the nuclear fuel cycle and some of the recent proposed developments that affect spent fuel disposition are described in Chapter 2.
Specific initiatives that have been proposed in recent years since the publication of the document under [5] in order to make the fuel cycle more international are discussed in Chapter 3. Most of these multinational approaches have been focused on controlling the front end of the fuel cycle (enrichment) and on reprocessing, since these are the most sensitive technologies that would clearly be best restricted to a limited number of locations. The focus of the present report, however, is on the specific impacts of the proposed approaches on spent fuel disposition, and especially on the feasibility of multinational geological repositories.
Chapter 4 discusses the disposition-specific aspects of the recent multinational initiatives.
Selected critical issues to be faced in implementing multinational repositories are addressed in Chapter 5. Finally in Chapter 6 conclusions are formulated and suggestions are made for the future.
2. NUCLEAR POWER AND NUCLEAR FUEL CYCLE DEVELOPMENTS AS DRIVERS FOR MULTINATIONAL INITIATIVES
2.1. Introduction
In choosing their policies for the peaceful use of nuclear energy, states make decisions exercising their sovereign rights, taking into account also their international treaty commitments under, for example the NPT. They may, in principle, choose to pursue purely national nuclear programmes under their exclusive control to meet their nuclear energy generation requirements. Proposals have however been made to restrict the further spread of sensitive technologies that could give a capability for weapons production to additional countries. Measures that can be taken to ensure that restrictions do not affect security of fuel supply include supplementing the commercial market with assurance of supply mechanisms, such as backup guarantees by governments and reserves of nuclear material under IAEA auspices [12]. The IAEA refers to “sensitive technological areas” relevant to the application of safeguards as being: (a) uranium enrichment; (b) reprocessing of spent fuel; (c) production of heavy water; and (d) handling of plutonium, including manufacture of plutonium and mixed uranium/plutonium fuel. [13]
However, spent fuel itself also contains fissile Pu and U, as well as extremely hazardous radioactive wastes. It can therefore present a security risk, in that — if not properly managed
— it could make nuclear proliferation by States or malevolent acts by terrorist groups more feasible. Moreover, the potential availability of spent fuel services to countries may assist in the decision for a country to introduce nuclear power. The chosen disposition route for spent fuel — what wastes will be disposed of and where — is therefore a crucial issue affecting the global development of nuclear power.
For some States, in particular for those not contemplating reprocessing, either because their inventories are too small or because continued use of nuclear power is not assured, direct disposal of spent nuclear fuel in a geological repository is an appropriate strategy. In fact, the most advanced programmes in Finland and Sweden are proceeding down this route.
However, nuclear power concepts now under development are aimed at closed fuel cycles requiring spent fuel processing and follow-on use of recovered nuclear materials in complementary nuclear reactors. As indicated above, for safety, security, non-proliferation and economic reasons, it might be best to limit the number of facilities for such advanced treatments.
For the same reasons, multinational disposal arrangements for spent fuel or waste products produced in its processing will also be increasingly necessary as nuclear power expands and as the new fuel cycle concepts are implemented. The clear increase in interest in using nuclear power and the goal of managing the expansion in ways that reduce risks of proliferation and terrorism are strong drivers for implementation of shared spent fuel disposition facilities;
spent fuel disposition services that include disposal will be part of the new nuclear power deployment paradigm.
Ultimately, a credible waste solution must include three elements:
• a technological and safety approach that will assure the public health and welfare and protect the environment;
• an institutional framework that will secure the benefits of the waste solution chosen, with clearly defined rights and responsibilities that are acknowledged and accepted by all parties, providing reliable disposition at affordable costs and providing sustainable performance throughout all phases of operation; and
• the scientific and technical capabilities and industrial facilities needed to implement the strategy, including a geological repository for long-lived nuclear waste.
2.2. Technological spent fuel disposition options
As shown in Table 1, today there are two currently implemented technological spent fuel disposition alternatives and a third is under development.
TABLE 1. TECHNOLOGICAL ALTERNATIVES FOR SPENT FUEL DISPOSITION
Spent fuel disposition strategy Comments
(1) Direct disposal of spent fuel assemblies in a
geological repository Technically relatively straightforward to implement;
requires long interim storage or else poses demanding heat load on geological repository; makes least use of potential energy of nuclear fuel; establishes “plutonium mine” in long term. Major societal challenges in siting.
(2) Reprocess using Purex process and recycle Pu and/or reprocessed uranium; vitrified waste to be disposed of in a geological repository
Reduces volume of high level waste; reduces radiotoxicity of repository inventory and needs less time to reach toxicity comparable to natural uranium; reduces heat burden; increases energy utilization; raises proliferation threat through use of sensitive technology; raises threat of nuclear terrorism. Major societal challenges in siting.
(3) Reprocess to partition uranium and all transuranics;
recycle uranium, consume transuranics in fast spectrum reactor; vitrified waste to be disposed of in a geological repository
R&D and commercial investment is necessary to establish industrial viability; advanced fuel cycles potentially offer possibilities for various strategic choices regarding uranium resources and for optimization of waste repository sites and capacities, while keeping almost constant both the radiological impact of the repositories and the financial impact of the complete fuel cycle
All three technological alternatives for spent fuel and radioactive waste disposition lead to a need for geological disposal that will require safety demonstration. However, the radiotoxicity of wastes resulting from each technology will affect the repository designs differently.
Figure 1 shows how the residual radiotoxicity associated with the repository inventories for different disposition options will vary with time. From this observation one can conclude that option 3 offers potential advantages for the future, particularly in relation to the global expansion of nuclear power — but it can be implemented in full only some decades from now. Option 1 remains the baseline and the closest to implementation. Regardless of progress in Option 3, Option 1 will likely remain the preferred choice of some States. Option 2 is a transitional technology and, assuming that Option 3 is eventually shown to be technologically superior, and that the overall costs of nuclear power deployment under an arrangement designed around Option 3 are competitive with other arrangements, existing Option 2 facilities will likely be replaced by Option 3 technology as the Option 2 facilities retire from service.
It should however be noted that the radio-elements providing the highest radiotoxicity seldom turn out as the dominating elements in the long term safety assessment of disposal facilities.
The highest doses come from mobile fission and activation products.
2.3. Reactor technology considerations
At the end of 2008, there were 439 nuclear power reactors in operation around the world, 34 more under construction and nearly 250 more in various stages of planning. As nuclear power increases, the need to have responsible spent fuel disposition arrangements in effect will become more urgent – as long as suitable arrangements are not in place, some members of the public and political leaders will remain openly sceptical and opposed to further reliance on nuclear power. Delaying the implementation of responsible spent fuel disposition arrangements may therefore limit the contribution of nuclear power to global energy supplies.
The nuclear contribution to reducing greenhouses gases will not of its own, prevent global warming, but it is increasingly recognized as being a necessary part of the solution.
FIG. 1. Decrease with time of radiotoxicity associated with the repository inventories for different disposition options.
Most existing and almost all new reactors are water cooled reactors fuelled with natural or low enriched uranium fuel of UO2 oxide pellets clad in zirconium alloy. Originally
reprocessing spent fuel from such reactors was intended to produce plutonium that could be deployed as fuel in a future generation of fast reactors. Low uranium prices and unexpectedly slow growth in nuclear energy led to the introduction of fast reactors being delayed and, as a consequence, an alternative route for using the plutonium was developed. This involves the use of mixed plutonium-uranium oxide (MOX) fuel in the current and near future generations of reactors. Pressurized light water reactors (PWRs) can run with a part, or perhaps all, of their cores fuelled with MOX. Boiling light water reactors (BWRs) are also capable of using MOX fuel, but because more extensive control modifications are needed, are less suitable for this purpose. Next come Russian VVER reactors and pressurized heavy water reactors which could use MOX, but do not at present do so. Important in the present context is the impact of MOX usage on spent fuel disposition. Direct disposal of spent MOX is feasible, although the higher heat loads and longer lived toxicity have implications on the design and operation of repositories. Current reprocessing facilities are capable of accepting MOX; hence there is also an alternative path forward for the current generation of nuclear plants. Future recycling capability to extract all transuranics will concentrate first on the current reactors.
Spent MOX fuel does pose additional reprocessing complications and, as of today, burning MOX repeatedly brings reduced reactivity and increased radiological burdens. The 239Pu content is reduced to 60% or less, and the percentage of the even isotopes, 238, 240 and 242, increases, adding neutron dose to workers. Until partitioning and transmutation is available, multiple MOX recycle will likely not be practical.
The long working life of current reactors and especially their lifetime extensions to 60 years (with additional extensions under consideration) implies that they will be the workhorses for the future of nuclear power over the next decades. New reactors may use different fuel forms for which there is currently no option other than direct disposal of spent fuel. The new reactors will included gas-cooled pebble bed reactors under development in China and South Africa with UO2 fuels clad in pyrolytic carbon and silicon carbide; barge-mounted reactors with plate-type fuel; liquid metal or gas cooled fast reactors, and reactor concepts like the Atoms for Peace reactor, using zirconium cermet fuel with UO2 kernels. The volumes of spent fuel arising from these reactors, especially those designed for long core life, will be far less than for the workhorse LWRs and HWRs. The spent fuel from the new reactors can be stored until recycling technology is developed, or disposed of in a geological repository under disposition option 1.
The next (fourth) generation (Gen IV) of nuclear power reactors is aimed at greater safety margins, higher thermal efficiency and eventually breeding to prolong nuclear power beyond the era when uranium is relatively abundant and inexpensive. They will be used to consume the growing inventories of separated plutonium and some will feature closed fuel cycles including transmutation of transuranics. They may continue to use oxide fuels, or carbides, nitrides, metals or cermets, which will likely be processed using modified or different (e.g., pyroprocessing) recycle technologies. The programmes developing the new power reactors normally incorporate spent fuel disposition arrangements integrated with the reactor development activities. Spent fuel disposition is included in the Gen IV programme to assure that all issues affecting successful deployment are resolved early on. At present, none of these reactors, except the oxide fuelled variants, have a known spent fuel disposition technology on the planning horizon.
Significant efforts to develop advanced fuel cycles are also being made within the IAEA project, INPRO (International Project on Innovative Nuclear Reactors and Fuel Cycles) [14], established in 2001. The objective is to bring together technology holders and users so that
they can consider jointly the international and national actions required for achieving desired innovations in nuclear reactors and fuel cycles. As well as facilitating coordination and cooperation among the advanced nuclear nations, INPRO aims to address the specific needs of developing countries that are interested in innovative nuclear systems. Both Gen IV and INPRO have been recognized at the highest levels as being important for the continuing development of safe, innovative advanced nuclear power systems.
2.4. Impacts of new reactors and fuel cycles on geological disposal
The developments in reactor and fuel cycle technologies will have direct impacts on disposal, in both a technical and a strategic manner. At a technical level, the advanced approaches will change the nature and the volumes of long-lived radioactive wastes. Positive aspects are that smaller or fewer geological repositories may be needed. However, the new waste forms need to be properly characterized, in particular with respect to their long term behaviour. As illustrated in Figure 1, shorter toxic lifetimes can result and this may ease the problems of finding suitable repository sites and of developing expensive, long-lived engineered barriers.
The expanding variety of fuel and waste types implies that handling and disposal facilities must be polyvalent. The technical advantages that advanced reprocessing methods and transmutation can bring in waste disposal may not be available for all types of advanced fuels.
In any case, the scientific and engineering facilities needed to cope with diverse future fuel and waste streams will place new demands on the technical capabilities of the organizations treating the wastes and ultimately carrying out disposal. As discussed below, most of these technological developments increase the arguments in favour of shared repositories that avoid the necessity for all nuclear power programmes, however small, to develop all of the required technologies.
The new possibilities opened by reactor and fuel cycle developments influence strategic as well as technical thinking on disposition options. In particular, disposal strategies may change; spent fuel may become less of a liability and more of an asset, so that direct disposal will become less attractive. A key point, however, is that they do not eliminate the need for geological disposal. There are extensive inventories of existing spent fuel or wastes where new technologies can not be retroactively applied. Furthermore, none of the advanced treatments will eliminate all long lived wastes resulting from nuclear power generation.
Lastly, other nuclear technologies also produce long-lived wastes that must be emplaced in geological repositories.
Recently, two studies were carried out to examine the impacts of advanced fuel cycles on radioactive waste policies and in particular on the disposal.
The first study, performed by a group of experts under the umbrella of the NEA Nuclear Development Committee, was published by the OECD mid-2006 [15]. Altogether 13 advanced fuel cycles within three families to illustrate differences between various technologies and levels of recycling capability were investigated and analyzed to assess their qualitative and quantitative impacts on the performance of different repository concepts. The fuel cycle schemes considered include options already at the industrial and commercial development stage, as well as very innovative variants which have not yet been fully demonstrated. Four schemes were chosen for comparison using selected 11 comparative assessment indicators:
• 1a (“once-through” PWR reactor, reference)
• 1b (Pu recycled once in the MOX for PWR)
• 2a (multi-recycling of Pu in the MOX for PWR)
• 3cV1 (all actinides recycling into carbide fuel for gas-cooled fast reactor)
The HLW repositories assessed in the study cover various deep geological formations that are considered adequate for long-term isolation of radioactive waste from the biosphere. The assessment was carried out for hypothetical, conceptual repositories in granite, salt, clay and tuff formations.
Although the emphasis within the study was on HLW, the impacts of advanced fuel cycle schemes on LILW generation, management and disposal were also briefly addressed. Results indicated that issues raised by secondary waste should not be neglected, in particular for innovative schemes leading to the generation of new types of waste with new chemical and isotopic compositions.
The main objective of the second study – Impact of Partitioning, Transmutation and Waste Reduction Technologies on the Final Nuclear Waste Disposal (RED-IMPACT) – was to investigate the impact of nuclear fuel cycles including partitioning and transmutation on the subsequent management of the radioactive waste. The synthesis report was published at the end of 2008 [16]. The basic approach was to compare issues related to radioactive waste management in a "once-through" fuel cycle with those for advanced nuclear fuel cycles. In the terminology of the RED-IMPACT project, the reference "once-through" fuel cycle was called scenario A1. Similarly to the NEA study, RED-IMPACT divided the fuel cycle schemes (called “scenarios” here) into two basic groups “industrial” and “more innovative”.
Consequently, the impacts of five scenarios were analyzed:
• A1 – direct disposal of spent fuel with no reprocessing
• A2 – all spent PWR fuel is recycled once and the MOX spent fuel is disposed of directly after its reuse in PWR; the inventory for disposal includes spent MOX fuel, vitrified waste from reprocessing and LILW arising from reprocessing
• A3 –Pu and U are recycled in a fast reactor; disposal is only for HLW (containing all the minor actinides) and LILW
• B1 – similar to A3 but the minor actinides are also recovered by reprocessing and recycled in the fast reactor
• B2 – involves a combination of LWRs, reprocessing, and an Accelerator Driven System (ADS); disposal of HLW from reprocessing of UO2, MOX and ADS fuel elements, plus LILW
The project led to complex assessment of the impact on waste management prior disposal, repository design, long term safety and management of LILW, taking into account three alternative environments for geological disposal: clay, granite and salt [17].
The repository design considerations focused on the thermal impact of the new waste forms on the dimensions of the repository. The main results are summarized in Table 2.
For disposal in granite and clay, the radiological consequences of the disposal of HLW and spent fuel were analyzed for the case of the normal evolution scenario; for disposal in salt a brine intrusion scenario was analyzed, because no release of radionuclides from the salt dome is expected as long as the salt dome remains intact. The main conclusion that can be drawn from the dose calculations performed for disposal in granite, clay and salt is that the introduction of advanced fuel cycles has only a limited impact on the doses resulting from the geological disposal of the corresponding high-level waste or spent fuel. This is because the
doses are essentially due to mobile fission and activation products. The amount of these products generated is not significantly influenced by the introduction of advanced fuel cycle scenarios.
TABLE 2. MAIN RESULTS OBTAINED WITHIN THE STUDY (ALL INDICATORS ARE GIVEN AS VALUES RELATIVE TO THE REFERENCE "ONCE THROUGH" FUEL CYCLE A1)
Gallery length
(clay, salt)
Maximum dose (granite)
Maximum dose (clay)
Cumulative released radiotoxicity (1 Ma, clay)
Radiotoxicity
after 500 a Human intrusion dose (500 a)
A1 (PWR) 1.00 1.000 1.000 1.0000 1.0000 1.0000
A2 (PWR, 1x recycle.
Pu) 0.97 0.316 0.316 0.164 0.803 2.72
A3 (FR, multi-recycle.
Pu) 0.59 0.231 0.160 0.0044 0.499 1.36
B1 (FR, multi-recycle.
Actinides 0.32 0.218 0.151 0.041 0.0042 0.0155
B2 (PWR + ADS) 0.49 0.11 0.130 0.040 0.0053 0.0818
The cumulative radiotoxicity released into the biosphere, integrated up to 1 million years, was calculated only for disposal in clay. It also strongly depends on the amount of 129I present in the disposed waste and consequently of the amount of spent fuel that is reprocessed. When looking at the results of the cumulative radiotoxicity released into the biosphere, one should note that during reprocessing a large fraction of the 129I is separated from the high-level radioactive waste and is either directly discharged or conditioned in a matrix that will also have to be disposed of somewhere. The radiotoxicity in the high level waste or spent fuel at 500 years is drastically reduced by including an ADS or fast reactors in the fuel cycle. This is true also for the doses calculated for human intrusion.
A key general point emerging from both studies is that none of the advanced fuel cycle technologies eliminates the need for geological disposal. None of the advanced treatments eliminates all long lived wastes resulting from nuclear power generation. Moreover, there are extensive inventories of existing spent fuel or wastes where new technologies can not be retroactively applied. Lastly, other nuclear technologies also produce long-lived wastes that must be emplaced in geological repositories.
2.5. Influence of new fuel cycles on multinational approaches
The advanced technologies and complex infrastructures needed for preparing new fuels and for advanced processing of spent fuel imply that multinational approaches will almost certainly be necessary in these areas since the capabilities will not be established in all countries. Although States may, in theory, still today decide to implement their own reprocessing plants, indigenous fuel cycle arrangements in all countries are unlikely in a scenario with greatly increased nuclear power and new processing technologies. For disposal, the situation may be different. At one extreme, new developments of the type discussed could, in principle, have impacts on national disposal planning – but little or no impact on multinational approaches. States may still opt to dispose of their own spent fuel or may agree to accept returned wastes from reprocessing and dispose of these in a national repository. In practice, however, multinational approaches are likely to be increasingly attractive throughout the whole backend, including disposal. Nuclear fuel suppliers may become more willing to accept returned spent fuel if advanced processing can extract more valuable recyclable
foreseen for non-fissile, relatively short-lived wastes, the range of potential host countries becomes wider. Flexible integrated schemes with different repository types being allocated to different host countries may become more feasible.
Mechanisms may be identified in which one or more States agree to share certain aspects of a spent fuel disposition arrangement that will be carried out in specified locations. Depending on the timing, economics and reliability of this combined system, States that agree to be only users of nuclear power may decide to require advantageous spent fuel disposition arrangements. The key requirements may be assurances of fresh fuel supply and of a disposition route for the radioactive wastes. The driving factors in such decisions include the following:
(a) Until States having nuclear power define their strategies and engage in programmes that will provide a safe disposition solution, “the spent fuel problem” will continue to be considered, to be unsolved. This will undermine public acceptance and thereby impede the acceptance of nuclear power. Introduction of new nuclear capacity will be more acceptable with a credible multinational disposition strategy than with no strategy or a national strategy that is clearly realisable only at very long times and very high costs.
(b) The wish to recover from its spent fuel materials (Pu and U) that can be re-used in energy production may lead a State to reprocess its inventory. However, reprocessing can also be pursued to provide weapon materials. Spreading reprocessing technology may raise risks of proliferation, and reprocessing plants, separated plutonium and hazardous radioactive materials, may be targets for terrorists.
(c) Spent fuel and HLW inventories themselves represent a potential terrorist target for sabotage, through the intentional dispersal of hazardous radioactive material.
Maintaining adequate physical protection at an operating reactor is necessary in any case to protect the reactor, its core inventory of nuclear material and any fresh fuel stored at the nuclear power plant, especially fresh MOX fuel. If the spent fuel remains at the nuclear power plant after the reactors are shut down and decommissioned, the likelihood of adequate protection may decrease over time.
(d) Dry or wet spent fuel storage technologies provide practical means to construct increased storage capacity that is affordable and within the technological means of most States. Using additional wet or dry spent fuel storage could allow a State to postpone repository decisions. Prolonged postponements may be attractive in the short term but may raise or exacerbate the security concerns noted above.
Any of the disposition paths mentioned in this Chapter may be taken by individual States to meet their national requirements in any of the ways described in the IAEA studies on multinational storage or disposal [5, 7]. Any individual State, could, if it so desired, provide services to other States. A group of States could cooperate in creating arrangements to meet the needs of the participating States, sharing the costs and responsibilities, and the group of States could decide to offer spent fuel disposition services to other States. A global solution to solving the spent fuel disposition problem could consist of a mixture of these approaches offering assurance to all participants.
However, siting a repository is politically contentious under the best of circumstances and engaging additional States in a multinational process that attempts to fix the conditions of service over the time scales involved may be much more complicated, depending on how the terms are fixed initially and the changes that occur over time. Nevertheless, sharing facilities brings obvious economic, technological, security and environmental benefits if a reliable scheme can be instituted that will weather changes in need, competition, economic well-
